Diaphragm of telephonic receivers and like instruments.



A. MARR.

DIAPHRAGM 0F TELEPHONIO RECEIVERS AND LIKE INSTRUMENTS.

APPLIOATION IILBD SEPT. 12,1912.

1,061,766. Pa ented May13,1913.

1 F il /hares: FL I 1.9 9

PATENT orrion.

UNITEDLSTATES ALEXANDER MARE, OF. MANCHESTER, ENGLAND.

DIAPHRAGM F TELEPHO'NIC RECEIVERS AND LIKE INSTRUMENTS.

vented new and useful Improvements in and Relating to the Diaphragms ofTelephonic Receivers and ,..Like Instruments, of which the following isa specification.

This. invention relates to improvements in the method of and means formounting the diaphragms of telephonic receivers, transmitters, talkingmachines, and the like or other diaphragm instruments which diaphragmsare supported at and around their peripheries only. I

Accordin to my invention a diaphragm is mounted 1n place by beingsecured around its edge or periphery between two opposed surfaces whichcome into contact only with the extreme peripheral corners of-each faceof the diaphragm.

The accompanying drawings illustrate various methods of and means forcarrying my invention into effect and will now be referred to.

. Figures 1 and 2 illustrate in cross section and in plan a ring or thelike in which adiaphragm is secured according to this invention. Figs. 3and 4 illustrate in section parts of'a telephonic receiver andillustrate different ways of securing in place in such an instrument,the diaphragm and fing of Figs. 1 and 2. Fig. 5 shows in cross section amodified form of ring for receiving the diaphragm. Fig. 6 shows in crosssection a diaphragm properly held in place in the modified ring of Fig.5. Figs. 7 8 and 10 show in section various further modifications of themode of securing the diaphragm in place. Fig. 9 is an enlarged View insection of part'of a dia hragmtand ring combined according to th shows astill further modification.

In particularly describing how this invention is carried into effect Iwill refer first to Figs. 1, 2 and 9. E represents a brass ring having ashallow V-shaped groove turned around it on its inner face. The extremediameter of this grooved part of the ring is such that the angle of theV will ,make tight contact with the peripheral corners of the diaphragmC as shown in Fig. 1, and in part to a larger scale, in Fig. 9. The ringE is divided as at F so that it can be sprung sufiiciently open to allowthe dia- Speoifloatlon of Letters Patent. I

. Applieation 'filnd September 12, 1912.

is invention. Fig. 11 A Patented May 13, 1913. Serial No. 719,962.

phragm to be put into or removed from place. This ring E carrying thedia hragm C may then be put in place between t e body A and cap B of areceiver as shown in Fig. 3 and be clamped between them in the manner inwhich a diaphragm is at present usually clamped. The diaphragm is andremains supported by the extreme peripheral corners of its faces only,and has the greatest freedom and amplitude of vibration.

Fig. 4 represents another method of combining a diaphragm carrying ringwith a receiver. In this arrangement the exterior of the ring E is screwthreaded and screws into a correspondingly screw threaded portion formedin the outer end of the body A. This screwed mode of attachment permitsthe easy and simple adjustment of the diap hragm relatively to themagnet pole G. he rin may be formed on its upper face with he es forengagement by any suitable tool for rotating it.

When a divided ring such as is shown in Fig. 2 is employed to hold thediaphragm, it maybe secured in its closed or gripping position by havingits ends soldered together or otherwise secured.

An undivided ring having a shallow V groove to grip the diaphragm may besuiticiently expanded by heat to enable it to be fitted over and aroundthe diaphragm.

In Fig. 5 is illustrated another form of ring E in which thegripillustrated to a large scale in Fig. 9 will eventually be 0btainedon the diaphragm. This ring is formed in its inner surface with acylindrical part 6 which rises upward from what, in Figs. 1 and 9, isthe bottom of the angle of the V shaped groove. This cylindrical part isof a diameter sufficient to allow the diaphragm to be put into place andrest upon the upper portion of the coned or contracted portion e of thering. When the diaphragm is so in place the upper or cylindrical part ofthe ring; (which has a surrounding portion roperly formed for thepurpose) is presse or spun over so that in COIlJllDCtlOIl with the conedpart c it eventually forms a V shaped groove around the inn... surfaceof the ring, in which groove the periphery of the ring is securely heldin the manner illustrated by Figs. 1 and 9. See Fig. 6. The ring E ofFigs. 5 and 6 is not divided.

place in a ring which is formed with a lower of the ring R. Theperipheral corners of the faces of the diaphragm are gripped be tweenthe opposed conical portions of the rings E E as shown in Fig. 7, asimilar grip being obtained to that shown in the large scale of Fig. 9.

The portions I; and E of the ring may be soldered together to maintainthe proper gri 'i on the liaphragm, or the grip may be maintained by thepressure of the screw cap of the instrument.

Vith a diaphragm held between two ring members as shown in Fig. 7 itispreferred to place a definite weight upon the top ring member E while itis loose and separate from the lower one E and then to secure the twomembers together while the top member is so weighted. As shown in Fig. 8the top member may form a plate J extending over and covering thediaphragm C except fOr a sound hole J in the center. As shown in Fig. 8the two ring components are secured together by pins D.

In Fig. 10 the two ring components are shown as having grooves F formedon their adjacent surfaces. hen the components are in the positionsshown the single groove I produced can be filled with cement pouredthrough a suitable hole. IVhen the cement sets the components are lockedtogether.

In the modification shown in Fig. 11 the plate J of the top ringcomponent has a ring of small holes J 2 bored tl'n'ough it. The cap 13has an inwardly expanding central sound hole which embraces the ring orholes .l'-..

The end of the magnet pole G in a telephonic receiver in which theimproved method of and means for mounting a diaphragm are employed maybe made spherically concave. so as to be about. cmiccntric with thecurve assumed by the diaphragm when it is in its nearest position to themagnet.

The edge of the diaphragm is preferably turned or trued up so that itextends at right angles across the diaphragm from face to face and formsright angled corners to r make tight contact with the beveled walls ofthe groove in which it is held. See the enlarged section in Fig. 9.

Although the description of the improved method of and means formounting the diaphragm with reference to the drawings has only referredto the magnetic diaphragms of telephonic receivers itis to be understoodthat like methods and means are applicable to the diaphragms of allinstruments which have vibratory diaphragms.

What. I claim is 1. In combination, a vibratory diaphragm and anencircling holder which grips the diaphragm only around the extremeperipheral corners of both faces substantially as set forth.

2. In combination, a vibratory diaphragm and an encircling holdertherefor to grip the diaphragm only around the extreme peripheries ofboth faces, such encircling holder being a ring with a V shaped grooveformed on its inner surface, substantially as set forth.

3. In combination. a vibratory diaphragm and an encircling holdertherefor to grip the diaphragm only around the extreme peripheralcorners of both faces such encircling holder comprising two ringcomponents one of which is fitted into the other, both being providedwith beveled surfaces to make tight contact with said corners,substantially as set forth.

In witness whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

. ALEXANDER- MARR.

Witnesses:

LU'IIIER J. Palm, CHAS. N. Daxuns.

